mod_audit: Support for adding location (GeoIP) to audit events This can be more privacy-friendly than logging full IP addresses, and also more informative to a user - IP addresses don't mean much to the average person, however if they see activity from outside their expected country, they can immediately identify suspicious activity. As with IPs, this field is configurable for deployments that would like to disable it. Location is also not logged when the geoip library is not available.

This module logs events where more than a certain amount of CPU time was
spent.

``` lua
log_cpu_threshold = 0.01 -- in seconds, so this is 10 milliseconds
```

Uses the Lua
[`os.clock()`](http://www.lua.org/manual/5.2/manual.html#pdf-os.clock)
function to estimate CPU usage.